Method of handling measurement capability and related communication device

ABSTRACT

A method of handling measurement capability for a mobile device capable of communicating with a network through a plurality of component carriers in a wireless communication system is disclosed. The method comprises receiving a measurement command from the network, and performing an inter-frequency measurement without measurement gap configured to any of the plurality of component carriers according to the measurement command, when the mobile device receives data on less than all of the plurality of component carriers.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a division of U.S. application Ser. No. 12/760,570filed on Apr. 15, 2010, which claims the benefit of U.S. ProvisionalApplication No. 61/169,319, filed on Apr. 15, 2009.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The application relates to a method utilized in a wireless communicationsystem and a communication device thereof, and more particularly, to amethod of handling measurement capability in a wireless communicationsystem and a related communication device.

2. Description of the Prior Art

A long-term evolution (LTE) system, initiated by the third generationpartnership project (3GPP), is now being regarded as a new radiointerface and radio network architecture that provides a high data rate,low latency, packet optimization, and improved system capacity andcoverage. In the LTE system, an evolved universal terrestrial radioaccess network (E-UTRAN) includes a plurality of evolved Node-Bs (eNBs)and communicates with a plurality of mobile stations, also referred asuser equipments (UEs).

In the LTE system, a user equipment (UE) may perform measurement tomeasure communication quality, such as quality of a frequency layer orstrength of a radio signal, which is controlled by the E-UTRAN, due tomobility of the UE. Measurement can be divided into two types accordingto the current operating frequency of the UE, which are anintra-frequency measurement and an inter-frequency/inter-RATmeasurement. The intra-frequency measurement is predominantly performedfor the mobility within the same frequency layer (i.e. between cellswith the same carrier frequency), whereas the inter-frequency/inter-RATmeasurement is predominantly performed for the mobility betweendifferent frequency layers (i.e. between cells with a different carrierfrequency). In addition, the inter-frequency/inter-RAT measurement isperformed during uplink/downlink idle periods, such as a measurement gapconfigured by the network. During the measurement gap, both the uplinkand downlink transmissions are prohibited, and thereby theinter-frequency/inter-RAT measurement can be performed within themeasurement gap.

Toward advanced high-speed wireless communication system, such astransmitting data in a higher peak data rate, LTE-Advanced system isstandardized by the 3rd Generation Partnership Project (3GPP) as anenhancement of LTE system. LTE-Advanced system targets faster switchingbetween power states, improves performance at the cell edge, andincludes subjects, such as bandwidth extension, coordinated multipointtransmission/reception (COMP), uplink multiple input multiple output(MIMO), etc.

For bandwidth extension, carrier aggregation is introduced to theLTE-Advanced system for extension to wider bandwidth, where two or morecomponent carriers are aggregated, for supporting wider transmissionbandwidths (for example up to 100 MHz) and for spectrum aggregation.According to carrier aggregation capability, multiple component carriersare aggregated into overall wider bandwidth, where the UE can establishmultiple links corresponding to the multiple component carriers forsimultaneously receiving and/or transmitting.

In addition, COMP is considered for LTE-Advanced as a tool to improvecoverage of high data rates, cell edge throughput, and systemefficiency, which implies dynamic coordination among multiplegeographical separated points. That is, when an UE is in a cell-edgeregion, the UE is able to receive signal from multiple cells, and themultiple cells can receive transmission of the UE.

However, in the LTE system, measurement functionality is defined for theUE supporting a single component carrier. The network always configuresa measurement gap to the UE for the inter-frequency/inter-RATmeasurement. For the UE operated in the LTE-Advanced system, themeasurement functionality is not clear defined for the UE supportingmultiple component carriers. Improper configuration of the measurementgap may cause packet scheduling problems. Since datatransmission/reception cannot be performed during the measurement gap,transmission/reception performance of the UE is downgraded.

In addition, consider a scenario related to multimedia broadcastmulticast service (MBMS). The MBMS gives the opportunity to broadcast ormulticast TV, film, information such as free overnight transmission ofnewspaper in digital form and other media in these networks. Since theMBMS is a broadcast or multicast service, the network is unable to knowwhich one of the UEs receives the MBMS data when the MBMS is provided bythe network. This causes difficulty in measurement gap configuration forthe network.

SUMMARY OF THE INVENTION

An embodiment of the present invention discloses a method of handlingmeasurement capability for a mobile device capable of communicating witha network through a plurality of component carriers in a wirelesscommunication system. The method comprises receiving a measurementcommand from the network, and performing an inter-frequency measurementwithout measurement gap configured to any of the plurality of componentcarriers according to the measurement command, when the mobile devicereceives data on less than all of the plurality of component carriers.

An embodiment of the present invention further discloses a method ofhandling measurement capability for a mobile device capable ofcommunicating with a network through a plurality of component carriersin a wireless communication system. The method comprises when the mobiledevice receives data with all of the plurality of component carriers,sending a message to notify the network that the mobile device receivesthe data with all of the plurality of component carriers, wherein themessage further indicates to the network that a measurement gap isrequired for an inter-frequency measurement, and performing theinter-frequency measurement on one of the plurality of componentcarriers when the network configures the measurement gap to thecomponent carrier.

An embodiment of the present invention further discloses a communicationdevice of a wireless communication system for handling measurementcapability. The communication device is capable of communicating with anetwork through a plurality of component carriers in the wirelesscommunication system and comprises means for receiving a measurementcommand from the network, and means for performing an inter-frequencymeasurement without measurement gap configured to any of the pluralityof component carriers according to the measurement command when thecommunication device receives data on less than all of the plurality ofcomponent carriers.

An embodiment of the present invention further discloses a communicationdevice of a wireless communication system for handling measurementcapability. The communication device is capable of communicating with anetwork through a plurality of component carriers in the wirelesscommunication system and comprises means for sending a message to notifythe network that the communication device receives the data with all ofthe plurality of component carriers when the communication devicereceives data with all of the plurality of component carriers, whereinthe message further indicates to the network that a measurement gap isrequired for an inter-frequency measurement, and means for performingthe inter-frequency measurement on one of the plurality of componentcarriers when the network configures the measurement gap to thecomponent carrier.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a wireless communication system.

FIG. 2 is a schematic diagram of an exemplary communication deviceaccording to the present disclosure.

FIGS. 3-7 are flowcharts of exemplary processes according to the presentdisclosure.

DETAILED DESCRIPTION

Please refer to FIG. 1, which illustrates a schematic diagram of awireless communication system featuring multiple connections between amobile device 10 and cells C1-Cn. The wireless communication system maybe a LTE-Advanced system. The mobile device 10 can operate with carrieraggregation and COMP. In FIG. 1, the mobile device 10 communicates withthe cells C1-Cn through radio links L1-Lm that correspond to componentcarriers CA(1)-CA(m) configured in the mobile device 10 respectively.Each of the component carriers CA(1)-CA(m) corresponds to a radiofrequency (RF) channel whose bandwidth may be varied according todifferent communication systems. In addition, the mobile device 10 isreferred as a user equipment (UE) or a mobile station (MS), and can be adevice such as a mobile phone, a computer system, etc. The mobile device10 may perform inter-frequency measurement for measuring signal strengthof a component carrier which has different carrier frequency fromfrequencies of the component carriers CA(1)-CA(m), or perform inter-RATmeasurement for measuring a component carrier CA(m+1) except thecomponent carriers CA(1)-CA(m).

FIG. 2 illustrates a schematic diagram of an exemplary communicationdevice 20. The communication device 20 can be the mobile device 10 shownin FIG. 1, but is not limited herein. The communication device 20 mayinclude a processing means 200 such as a microprocessor or ASIC, astorage unit 210 and a communication interfacing unit 220. The storageunit 210 may be any data storage device that can store program code 214,for access by the processing means 200. Examples of the storage unit 210include but are not limited to a subscriber identity module (SIM),read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetictapes, hard disks, and optical data storage devices. The communicationinterfacing unit 220 is preferably a radio transceiver and can exchangewireless signals with the network according to processing results of theprocessing means 200.

The program code 214 includes a program code of a RRC layer which canactivate measurement functionality according to measurementconfigurations received from the network. The RRC layer is used forperforming RRC connection management, measurement control and reporting,and radio bearer (RB) control responsible for generating or releasingradio bearers (RBs). In addition, the RRC layer includes a RRC_CONNECTEDstate capable of using the RBs, and a RRC_IDLE state incapable of usingthe RBs.

For measurement mechanism in the LTE-Advanced system, the applicanttakes measurement capability of the UE into consideration. Assume that aUE of the LTE-Advanced system supports two component carriers. If the UEreceives data only on one of the component carriers, the UE shall beable to perform the inter-frequency/inter-RAT measurement withoutmeasurement gap assistance of the network. That is, the network does notnecessarily configure the measurement gap to the UE for theinter-frequency/inter-RAT measurement. As a result, a basis formeasurement gap configuration determination is required for the networkin the LTE-Advanced system.

In addition, the UE shall provide proper information to the network sothat the network can know the usage status of the component carriers ofthe UE. Therefore, the network can correctly determine whether ameasurement gap is required for the UE for the inter-frequency/inter-RATmeasurement. Thus, how to transfer the information to the network isalso provided herein.

Please refer to FIG. 3, which illustrates a flowchart of an exemplaryprocess 30. The process 30 is utilized in the network for handlingmeasurement capability of a UE capable of supporting a maximum number ofcomponent carriers in a wireless communication system, in order toprovide a criterion for measurement gap configuration determination. Thenetwork may be an evolved Node-B (eNB) or a cell (e.g. any of the cellsC1-Cn). The process 30 can be compiled into the program code 214 andincludes the following steps:

Step 300: Start.

Step 310: Receive a capability information message indicating acomponent carrier capability, from the UE.

Step 320: Determine whether to configure a measurement gap to at leastone of the component carriers, according to the component carriercapability and a first number of component carriers that have beenconfigured to the UE.

Step 330: End.

According to the process 30, the network determines whether to configurethe measurement gap to at least one of the component carriers accordingto the component carrier capability which may include the maximum numberof the component carriers on which the UE receives data and according tothe first number of component carriers that the network configures tothe UE to receive data.

The measurement gap configuration determination is described as follows.After the network receives the capability information message indicatingthe component carrier capability, the network compares the maximumnumber of the component carriers indicated by the component carriercapability and the first number of component carriers having beenconfigured to receive data. If the first number of component carriersthat have been configured to receive data is equal to the maximum numberof the indicated component carriers, the network configures themeasurement gap to at least one of the component carriers. That is, thenetwork configures the measurement gap(s) to at least one of thecomponent carriers for the inter-frequency/inter-RAT measurement whenthe UE receives data with the maximum number of the component carriers.On the other hand, the network does not configure the measurement gap toany of the component carriers for the inter-frequency/inter-RATmeasurement when the UE receives data on part of the component carriers.With such manner, the network can properly configure the measurement gapto each component carrier of the UE for the inter-frequency/inter-RATmeasurement.

Referring back to FIG. 1, take an example based on the concept of theprocess 30. As shown in FIG. 1, the UE supports m component carriersCA(1)-CA(m), thereby capable of receiving data on the m componentcarriers CA(1)-CA(m). The network receives the capability informationmessage indicating the component carrier capability including the numberof “m” from the UE, and the network compares the “m” and the number ofcomponent carriers that has been configured to the UE to receive data.If the network has configured (m−1) component carriers CA(1)-CA(m−1) toreceive data, the network does not configure the measurement gap to theUE for the inter-frequency/inter-RAT measurement. On the other hand, ifthe network has configured all the component carriers to the UE forreceiving data, the network configures the measurement gap to at leastone of the component carriers of the UE for inter-frequency/inter-RATmeasurement.

In addition, when no measurement gap is configured to the UE, thenetwork can send a measurement command to command the UE to perform theinter-frequency measurement/inter-RAT measurement on at least one of thecomponent carriers. Therefore, when the UE is not configured to receivedata with the maximum number of the component carriers, the UE canperform the inter-frequency measurement/inter-RAT measurement withoutmeasurement gap assistance of the network. For example, when the UEreceives data on the component carriers CA(1)-CA(m−1), the network doesnot configure any measurement gap to the UE, but sends the measurementcommand to command the UE to perform the inter-frequencymeasurement/inter-RAT measurement on the component carrier CA(m) that isnot in-use for data reception. Please note that, the measurement commandcan command the UE to perform the inter-frequency measurement/inter-RATmeasurement on any of the component carriers that are not configured toreceive data. For example, if the UE is configured to receive data onlyon the component carrier CA(1), the network can command the UE toperform the inter-frequency measurement/inter-RAT measurement on any ofthe component carriers CA(2)-CA(m) via the measurement command.

Alternatively, the network configures the measurement gap for theinter-frequency/inter-RAT measurement when a message indicating that allof the component carriers are configured to receive data is receivedfrom the UE. That is, the UE sends the message to the network to notifythat the UE receives data with the maximum number of the componentcarriers, and thereby the network configures the measurement gap to atleast one of the component carriers. In addition, the message mayfurther indicate to the network that the measurement gap is required forthe inter-frequency/inter-RAT measurement. Therefore, the network cantimely configure the measurement gap for the inter-frequency/inter-RATmeasurement.

As the above mentioned, the measurement gap can be configured to ones ofthe component carriers. The component carriers that are configured withthe measurement gap cannot perform data transmission/reception withinthe measurement gap, but only perform the inter-frequency/inter-RATmeasurement. On the other hand, the un-configured component carriers cancontinue the data transmission/reception without measurement gapinfluence, thereby increasing usage efficiency of the component carriersof the UE. For example, the UE supporting data reception on m componentcarriers receives data on all of the component carriers CA(1)-CA(m).When the network requires the UE to perform theinter-frequency/inter-RAT measurement for a certain component carrier(e.g. a component carrier CA(m+1) shown in FIG. 1), which is notbelonging to the component carriers CA(1)-CA(m), the network canconfigure the measurement gap only to a component carrier (e.g. thecomponent carrier CA(1)). Therefore, the component carriers CA(2)-CA(m)are not affected by the measurement gap, and remains performing the datatransmission/reception.

In addition, the network determines that the component carriercapability of the UE is changed, when reception of a multimediabroadcast multicast service (MBMS) message of the UE is activated onones of the component carriers. The activated component carriers can bea dedicated component carrier only used for transmitting the MBMSmessage to the UE, or a mixed component carrier used for transmittingthe MBMS message and unicast data to the UE. If the activated componentcarrier is the dedicated component carrier, the network determines thatthe maximum number of the component carriers that the UE is capable ofusing is changed. On the other hand, if the activated component carrieris the mixed component carrier, the network does not determine themaximum number of component carriers that the UE is capable of using ischanged, and may configure the UE to remove the mixed component carrierfor unicast data transmission.

For clearly understanding the MBMS message reception activation, pleaserefer to FIG. 4, which illustrates a flowchart of an exemplary process40. The process 40 is utilized in the UE capable of supporting a maximumnumber of component carriers for handling measurement capability. Theprocess 40 can be compiled into the program code 214 and includes thefollowing steps:

Step 400: Start.

Step 410: Send a capability information message indicating a componentcarrier capability to the network.

Step 420: Indicate to the network that the component carrier capabilityis changed, when one of the component carriers is dedicated to MBMStransmission.

Step 430: End.

According to the process 40, the UE not only indicates the componentcarrier capability to the network, but also indicates the change of thecomponent carrier capability to the network when the UE activates theMBMS reception on the dedicated component carrier(s).

Take an example associated with FIG. 1. The UE in a RRC_CONNECTED statesupports m component carriers CA(1)-CA(m). When the UE sends thecapability information message indicating the component carriercapability (e.g. the total number of the component carriersCA(1)-CA(m)), the network determines to configure the measurement gap toat least one of the component carriers CA(1)-CA(m) according to thecomponent carrier capability and the number of the component carriershaving been configured to the UE. The detailed description related tothe measurement gap configuration determination can be referred fromabove, so it is not given herein. If the network configures themeasurement gap to part of the component carriers, such as the componentcarrier CA(1), the UE performs the inter-frequency/inter-RAT measurementonly using the measurement gap on the component carrier CA(1), therebyavoiding affecting other component carriers (e.g. the component carrierCA(2)-CA(m)) for data transmission/reception. On the other hand, if thenetwork configures the measurement gap to all of the component carriersCA(1)-CA(m), the UE performs the inter-frequency/inter-RAT measurementusing the measurement gap on all of the component carriers CA(1)-CA(m).In addition, the UE indicates to the network that the component carriercapability is changed when the UE activates MBMS reception on thededicated component carrier(s). In addition, the UE indicates to thenetwork that the component carrier capability is (m−1) when the UEhaving one dedicated component carrier activates MBMS reception on thecomponent carrier, indicates to the network that the component carriercapability is (m−2) when the UE having two dedicated component carriersactivates MBMS reception on both the dedicated component carriers, andso on. Thus, the network can clearly know the latest component carriercapability of the UE, and determines whether to configure themeasurement gap for the inter-frequency/inter-RAT measurement accordingto the latest component carrier capability, thereby making measurementgap configuration correctly reflecting the component carrier usage ofthe UE.

Moreover, the UE may further indicate to the network frequencyinformation of the dedicated component carrier(s) on which the UEreceives the MBMS message from the network. Alternatively, the UE mayindicate to the network carrier information of the component carrier(s)on which the UE receives the MBMS message from the network. Please notethat, the carrier information may include frequency information of thecomponent carrier(s) on which the UE receives the MBMS message, and typeinformation indicating whether the component carrier(s) on which the UEreceives the MBMS message is the dedicated component carrier or themixed component carrier.

Please refer to FIG. 5, which illustrates a flowchart of an exemplaryprocess 50. The process 50 is utilized in the UE capable of supporting amaximum number of component carriers for handling measurementcapability. The process 50 can be compiled into the program code 214 andincludes the following steps:

Step 500: Start.

Step 510: Receive a measurement command from the network.

Step 520: Perform an inter-frequency measurement or the inter-RATmeasurement according to the measurement command when the UE does notreceive data with the maximum number of the component carriers.

Step 530: End.

According to the process 50, the UE performs theinter-frequency/inter-RAT measurement according to the measurementcommand received from the network without measurement gap configured toany of the component carriers when not all of the component carriers arein-use for data reception.

Take an example associated with FIG. 1. As the above mentioned, when theUE receives data on the component carriers CA(1)-CA(m−1), the networkdoes not configure any measurement gap to the UE. In addition, thenetwork can send the measurement command to command the UE to performthe inter-frequency/inter-RAT measurement on the component carrierCA(m). In other words, the UE can perform the inter-frequency/inter-RATmeasurement when the UE does not receive data on all of the componentcarriers CA(1)-CA(m). Please note that, the measurement command cancommand the UE to perform the inter-frequency/inter-RAT measurement onany of the component carrier(s) that is/are not configured to receivedata. The detailed description can be referred from above, so it is notgiven herein.

Based on the concept of the process 50, when the UE does not receivedata with the maximum number of the component carriers, the UE canperform the inter-frequency/inter-RAT measurement without measurementgap assistance of the network.

Please refer to FIG. 6, which illustrates a flowchart of an exemplaryprocess 60. The process 60 is utilized in the UE capable of supporting amaximum number of component carriers for handling measurementcapability. The process 60 can be compiled into the program code 214 andincludes the following steps:

Step 600: Start.

Step 610: Receive data with the maximum number of component carriers.

Step 620: Send a message to notify the network that the UE receives thedata with the maximum number of the component carriers, wherein themessage further indicates to the network that a measurement gap isrequired for an inter-frequency measurement or an inter-RAT measurement.

Step 630: Perform the inter-frequency measurement or the inter-RATmeasurement on one of the component carriers when the network configuresthe measurement gap to the component carrier.

Step 640: End.

According to the process 60, when the UE receives data with the maximumnumber of the component carriers, the UE sends the message to thenetwork for notifying that the UE receives data with the maximum numberof the component carriers.

For example, the UE receives data on all of the component carriersCA(1)-CA(m), and then sends the message to notify the network that theUE receives data on all of the component carriers CA(1)-CA(m). In otherwords, the message indicates to the network that the measurement gap isrequired for the inter-frequency/inter-RAT measurement. Therefore, thenetwork configures the measurement gap for the inter-frequency/inter-RATmeasurement according to the notification message. Please note that, thenetwork can configure the measurement gap to part or all of thecomponent carriers. The detailed description can be referred from above,so it is not given herein.

Please refer to FIG. 7, which illustrates a flowchart of an exemplaryprocess 70. The process 70 is utilized in the UE capable of supporting amaximum number of component carriers for handling measurementcapability. The process 70 can be compiled into the program code 214 andincludes the following steps:

Step 700: Start.

Step 710: Receive a MBMS message on one of the component carriers in aRRC_IDLE state, from the network.

Step 720: Send a capability information message indicating a componentcarrier capability to the network when the UE enters a RRC_CONNECTEDstate from the RRC_IDLE state, wherein the component carrier capabilityexcludes capability of the component carrier transmitting the MBMSmessage.

Step 730: End.

According to the process 70, when the UE in the RRC_IDLE state receivesthe MBMS message on any of the component carriers, the UE excludescapability of the component carrier(s) from the component carriercapability after entering the RRC_CONNECTED. In other words, After theUE enters the RRC_CONNECTED state from the RRC_IDLE state, the UE sendsthe capability information message indicating to the network thecomponent carrier capability which does not include the capability ofcomponent carrier(s) transmitting the MBMS message. That is, the UEtakes a change of the component carrier capability in the RRC_IDLE stateinto consideration when reporting to the network the component carriercapability in the RRC_CONNECTED state. Therefore, the network canacquire a reliable component carrier capability for the measurement gapconfiguration determination.

For example, the UE in the RRC_IDLE state receives the MBMS message onthe component carriers CA(1)-CA(5). When the UE enters the RRC_CONNECTEDstate, the UE sends the capability information message indicating thenumber of component carriers the UE supports is m−5 to the network.Accordingly, the network makes a determination of the measurement gapconfiguration according to the component carrier capability excludingthe capability of the component carriers CA(1)-CA(5).

The capability information message may further indicate frequencyinformation of the component carrier(s) transmitting the MBMS message.In addition, the component carrier(s) transmitting the MBMS message maybe a dedicated component carrier.

Please note that, the abovementioned steps of the processes includingsuggested steps can be realized by means that could be hardware,firmware known as a combination of a hardware device and computerinstructions and data that reside as read-only software on the hardwaredevice, or an electronic system. Examples of hardware can includeanalog, digital and mixed circuits known as microcircuit, microchip, orsilicon chip. Examples of the electronic system can include system onchip (SOC), system in package (Sip), computer on module (COM), and thecommunication device 20.

In conclusion, the exemplary examples and means are provided forhandling the measurement capability of the UE supporting data transferof multiple connections (e.g. multiple component carriers or COMP), soas to make a correct determination of measurement gap configuration tothe UE, thereby avoiding affecting schedule of the component carrier(s)of the UE.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. A method of handling measurement capability for amobile device capable of communicating with a network through aplurality of component carriers in a wireless communication system,comprising: receiving a measurement command from the network; andperforming an inter-frequency measurement without measurement gapconfigured to any of the plurality of component carriers according tothe measurement command, when the mobile device receives data on lessthan all of the plurality of component carriers.
 2. The method of claim1, further comprising: when the mobile device receives a multimediabroadcast multicast service (MBMS) message on a first number of theplurality of component carriers in a radio resource control (RRC) idlestate from the network and enters a RRC connected state from the RRCidle state, sending a capability information message indicating acomponent carrier capability to the network, wherein the componentcarrier capability indicates a second number of component carriers whichis equal to the number of all of the plurality of component carriersminus the first number of component carriers on which the MBMS messageis transmitted.
 3. The method of claim 2, wherein the capabilityinformation message further indicates frequency information associatedwith the second number of component carriers to the network.
 4. Themethod of claim 1, further comprising: performing an inter-frequencymeasurement with measurement gap configured to any of the plurality ofcomponent carriers according to the measurement command when thecommunication device receives data on all of the plurality of componentcarriers.
 5. A method of handling measurement capability for a mobiledevice capable of communicating with a network through a plurality ofcomponent carriers in a wireless communication system, comprising: whenthe mobile device receives data with all of the plurality of componentcarriers, sending a message to notify the network that the mobile devicereceives the data with all of the plurality of component carriers,wherein the message further indicates to the network that a measurementgap is required for an inter-frequency measurement; performing theinter-frequency measurement on one of the plurality of componentcarriers when the network configures the measurement gap to thecomponent carrier; and when the mobile device receives a multimediabroadcast multicast service (MBMS) message on a first number of theplurality of component carriers in a radio resource control (RRC) idlestate, from the network and enters a RRC connected state from the RRCidle state, sending a capability information message indicating acomponent carrier capability to the network, wherein the componentcarrier capability indicates a second number of component carriers whichis equal to the number of all of the plurality of component carriersminus the first number of component carriers on which the MBMS messageis transmitted.
 6. The method of claim 5, wherein the capabilityinformation message further indicates frequency information associatedwith the second number of component carriers to the network.
 7. Acommunication device capable of communicating with a network of awireless communication system through a plurality of component carriers,for handling measurement capability, comprising: a storage unit forstoring instructions of: receiving a measurement command from thenetwork; and performing an inter-frequency measurement withoutmeasurement gap configured to any of the plurality of component carriersaccording to the measurement command when the communication devicereceives data on less than all of the plurality of component carriers;and a processing means, coupled to the storage unit, configured toexecute the instructions stored in the storage unit.
 8. Thecommunication device of claim 7, wherein the storage unit further storesan instruction of: sending a capability information message indicating acomponent carrier capability to the network when the communicationdevice receives a multimedia broadcast multicast service (MBMS) messageon a first number of the plurality of component carriers in a radioresource control (RRC) idle state from the network and enters a RRCconnected state from the RRC idle state, wherein the component carriercapability indicates a second number of component carriers which isequal to the number of all of the plurality of component carriers minusthe first number of component carriers on which the MBMS message istransmitted.
 9. The communication device of claim 8, wherein thecapability information message further indicates frequency informationassociated with the second number of component carriers to the network.10. The communication device of claim 7, wherein the storage unitfurther stores an instruction of: performing an inter-frequencymeasurement with measurement gap configured to any of the plurality ofcomponent carriers according to the measurement command when thecommunication device receives data on all of the plurality of componentcarriers.
 11. A communication device of a wireless communication systemcapable of communicating with a network of a wireless communicationsystem through a plurality of component carriers, for handlingmeasurement capability, comprising: a storage unit for storinginstructions of: sending a message to notify the network that thecommunication device receives data with all of the plurality ofcomponent carriers when the communication device receives the data withall of the plurality of component carriers, wherein the message furtherindicates to the network that a measurement gap is required for aninter-frequency measurement; performing the inter-frequency measurementon one of the plurality of component carriers when the networkconfigures the measurement gap to the component carrier; and sending acapability information message indicating a component carrier capabilityto the network when the communication device receives a multimediabroadcast multicast service (MBMS) message on a first number of theplurality of component carriers in a radio resource control (RRC) idlestate from the network and enters a RRC connected state from the RRCidle state, wherein the component carrier capability indicates a secondnumber of component carriers which is equal to the number of all of theplurality of component carriers minus the first number of componentcarriers on which the MBMS message is transmitted; and a processingmeans, coupled to the storage unit, configured to execute theinstructions stored in the storage unit.
 12. The communication device ofclaim 11, wherein the capability information message further indicatesfrequency information associated with the second number of componentcarriers to the network.